The present invention relates generally to thermistor probes, and more specifically to a thermistor probe assembly and method for positioning and moisture proofing a thermistor probe assembly.
A thermistor probe is generally used for sensing a temperature response in a variety of applications, such as, for example, refrigeration, air conditioning and other cooling applications. A typical thermistor probe includes a thermistor element embedded inside a packaging for ruggedness. It has been found that sensor response varies based upon the location of the thermistor probe within the packaging. Conventional processes for packaging thermistor probes are manual, and hence the location of the thermistor probes within the packaging is entirely dependent upon the skill of the operator.
For measurement accuracy, it is useful if the packaging of a thermistor probe is moisture proof. In particular, when thermistor probes are used in low temperature applications, the insulation charactertistics of the thermistor probe is essential. In such environments any moisture ingress affects the electrical behaviour of the probe and therefore, the accuracy and reliability of its performance. Typically, the thermistor probe is sealed against moisture by disposing a shield on the thermistor probe using a multi-stage injection molding process. This manufacturing process requires a high cycle time and does not ensure repeatability in the accurate positioning of the thermistor inside the packaging.
Accordingly, there is a need in the art of manufacturing thermistor probes for an improved packaging technique that gives consistency in the measurement response by more accurately positioning the thermistor element inside the thermistor packaging at a desired position, while concurrently achieving moisture proofing with a lower production time.